RyanSS

How hard is it and what do i need to convert to speed density from MAF?
I just bought a TPI system from the junkyard and it is missing the MAF, just wondering if i should get a new one or convert to SD.
Thanx.

88 350 tpi formula

iTrader: (9)

I would just keep you mass air flow it will be easer from what I have heard you would need a new ecm and some pinning would be required. to your post I think that mass is better but, is way to limited in our cars however if you had the choice between an 89 and 90 tpi car and planed on modifying it quite a bit of the two map is better to have.there are much more programming options for you.

Kevin Irving

go here: http://www.ece.udel.edu/~davis/z28/

------------------
Kevin Irving
85 Trans Am WS-6, 305 TPI, custom burned '86 PROM with '87 "165"ECM, Accel Supercoil & 8.8 Wires, MSD 6AL, Aluminum Driveshaft, Wonderbar, TB Coolant Bypass, Ported Plenum, Modified MAF, Syclone Fuel Pump, JET Airfoil

15.556 @ 86.65mph, Nov 10, 2000.... I know it sucks.. but it will get better!

http://www.geocities.com/transam85tpi/

Member - The Tidewater Trans Am Club, Norfolk VA http://www.geocities.com/ttacva/

IROCZ88

SD is better. You need a new computer #1227730, map sensor which you can mount on the firewall and run a vacuum line to the back of the intake, and you need to send your wiring harness somewhere to be modified. Try www.howell-efi.com. The hardest part is removing the wiring harness.

------------------
'88 IROC TPI 355, '69 truck 4-bolt, fully balanced, 9.75:1 compression, fully ported '70 truck heads(for now), Harland Sharp 1.6 Roller Rockers, Comp Cams CS 252AH-12, ported '86 TPI converted to speed density, Crane AFPR, Flowmaster 3in. exhaust, Edelbrock TES headers, all emissions equipment is still intact, plan on burning my own chips, many more mods and parts on the way as time and money permits =(
Best E.T. with TBI 305: 16.11 @ 82mph
Haven't been to track with new motor
If you have any questions on converting from TBI to TPI email me at jdkchevy70@yahoo.com
In memory of Dale Earnhardt, I'll miss cheering for that black #3 on raceday!!!

86TpiTransAm

Everybody's always talkin' about "real world" numbers so I'm listing the track times from the above mentioned websites!! Some were run with the MAP and some with the MAF!! I don't see that big a difference really!! The guy who did these test says that he's done some work to the chip for the MAP since the run and that it runs at and above the level of the MAF but in all reality I don't think there's that much difference! And if you truly understand the equations and formulas of needed CFM, you'll see that a MAF sensor can flow more than enough air for just about any application!!

Oh yeah....how 'bout that GM crate engine....big block that produces 500+ HP, has TPI with only a 48mm TB AND a MAF!!
--------------------------------------------

1 (MAP) 13.098@105 (let car shift to OD)
2 (MAP) 13.095@105 (let car shift to OD)
3 (MAF) 12.941@105 (kept car in 3rd to 5600rpm)
4 (MAF) 13.071@103 (let car shift to OD)
5 (MAF) 12.927@106 (kept car in 3rd to 5800rpm)
6 (MAP) 13.063@105 (kept car in 3rd to 5800rpm)
7 (MAP) 13.050@105 (kept car in 3rd to 5600rpm)

Grim Reaper

Are you talking about the RamJet 502? If so, its MAP based as far as I know.

IROCZ88

RJ 502 is map based.

------------------
'88 IROC TPI 355, '69 truck 4-bolt, fully balanced, 9.75:1 compression, fully ported '70 truck heads(for now), Harland Sharp 1.6 Roller Rockers, Comp Cams CS 252AH-12, ported '86 TPI converted to speed density, Crane AFPR, Flowmaster 3in. exhaust, Edelbrock TES headers, all emissions equipment is still intact, plan on burning my own chips, many more mods and parts on the way as time and money permits =(
Best E.T. with TBI 305: 16.11 @ 82mph
Haven't been to track with new motor
If you have any questions on converting from TBI to TPI email me at jdkchevy70@yahoo.com
In memory of Dale Earnhardt, I'll miss cheering for that black #3 on raceday!!!

camaro6spd

yeah, but if modify the amount of air entering, the MAF will automatically adjust for the amount of air, SD will not, you will need to change the computer...

Kevin91Z

iTrader: (1)

Myths and rumors.

MAF is better than Speed Density, from a purely design standpoint. But when you're talking thirdgens, the Speed Density has MUCH more research put into it. All the aftermarket TPI stuff is Speed Density. Its really easy to tune when you're dealing with custom PROMs. The thirdgen MAF is great up to a point, but once you start making more power, the MAF becomes a restriction in the intake. Speed Density can handle lots of mods that you throw at it. My previous combo used a stock 305 5-speed chip to control a 350 with a ZZ4 cam, ZZ4 heads, and SLP 1 5/8" headers. But when I switched to an LT4 HOT cam, I needed to make my own PROM. Would a MAF have handled the combo? Who knows? Probably, but both MAF and MAP benefit from custom PROMs, when you start modifying the engine they're controlling.

Which is better? Whichever one you have... But if you're starting from scratch, Speed Density is the way to go.

------------------
West Coast GM Shootout 2001!
1991 Camaro Z28
5.7L 5-Speed (originally 305)
13.25 @ 107.18 MPH
Southern California
Member: SoCal 3rd Gen F-Bodies
Webmaster: SoCal F-Bodies
-=ICON Motorsports=-

a73camaro

I gotta laugh. All the Mustangs want to switch from MAF to SD systems.

[This message has been edited by a73camaro (edited April 05, 2001).]

Grim Reaper

Being an old "tuner" for the good old days, SD bears a much more direct relationship to my method of tuning. Yes, add a lumpy cam to a MAF system and you have problems too, possibly even more due to reversion in the intake which can cause its own problems.

The stock SD system also has a certain range of "operation" that allows you to make a certain level of mods without HAVING to burn a custom eprom. But personally, I prefer "tweaking and tuning" my engine and I am CONSTANTLY tweaking it down to the point to seeing the effects of weather and elevation. But as I make more "stats", I am also building up a database of mods to the MAT Inverse Look Up table that will give much more stable temperature correction factors from about -10F to 110*F. But you will have to wait another 6 months for the full adjustments.

Unfortunately, these correction factors will only be valid for the SD cars. I haven't played with these tables on MAF cars.

IROCZTWENTYGR8

iTrader: (1)

Which is better?? It depends who u ask really. I like MAF. I'd rather have a system that does the adjustments for u, than a system u have to buy stuff for and make your own. I also like the way the MAF looks better.

------------------
Looking For:

87 IROC-Z28 350 TPI
The car I want.

84 TRANS AM 305 H.O.
Another car that would be OK to own while I still look for the IROC-Z!!

JAY87GTA

I look at it this way. If SD was better, then all the new cars would run SD. But they don't. The LT1 and LS1 run MAF. I believe it is because MAF allows a more precise injector pulse width. All of the aftermarket systems run SD because of packaging and cost concerns. A good MAF costs aboutt $200. A MAP sensor costs about $15. Plus SD is easier to package. I think that with a proper PROM both systems will give you the same performance and economy, as long as the MAF does not become an intake restriction.

------------------
'87GTA w/ SLP Cold Air, MSD Coil, Airfoil, Gutted MAF, AFPR, TES Headers, HI-FLOW CAT, Flowmaster Catback, Energy Suspension Master Bushing Kit

IROCZTWENTYGR8

iTrader: (1)

I agree.

Any1 see the test TPIS did with the same engine, modded the same, 1 MAF, 1 SD though?? The MAF's #'s were better, and the MAF idled better also.

SD was put into Third Gens because it was cheaper to produce than MAF, not because it was better.

------------------
Looking For:

87 IROC-Z28 350 TPI
The car I want.

84 TRANS AM 305 H.O.
Another car that would be OK to own while I still look for the IROC-Z!!



[This message has been edited by IROCZTWENTYGR8 (edited April 05, 2001).]

Grim Reaper

The MAF system on 4th gens are light years ahead of anything that came on 3rd gens. You cannot compare the two systems...its like a compucarb to EFI and evolutionary change.

As for automatically adjusting, that is still a myth for even the new MAF. There are limits of how far you can go with a cam on an LS1 (the best of the breed) before the PCM must be reprogrammed too.

My biggest complaint with the thridgen MAF system is the 255 gm/sec limitation and the limited amount of space on the eprom to make code changes to fix this problem.

SDs biggest advantage (among 3rd gens) is its quicker responsiveness (along with plenty of extra room in the eprom for additional code). MAF is slower to react.

But when it comes to serious mods, BOTH need eprom changes, plain and simple.

Kevin91Z

iTrader: (1)

Yah, Glenn has it right. MAF *IS* the better of the two, like I said in my post. GM went back to MAF in the 94+ cars because it allows for better metering of the air and provides more accurate data. But when you're talking thirdgens, the SD computer is light years ahead of the MAF computer, just as the 94+ PCM is light years ahead of the thirdgen stuff. But do you need to switch on a stock or mild car? Nope. Do you need to switch on a heavily modified car? Maybe... The best reason to switch would be for 85 TPI cars wanting something better, or for carb guys going to EFI. For the 86-88 MAF guys, I recommend switching to the 89 ARAP chip and disabling your cold start injector. You'll be kicking *** then.

IROCZ88

I agree completely with Glenn91 and Kevin91Z. Yes, MAF is better, but when comparing the stock computers in thirdgens, SD is much more refined.
Is it true 5.0 Mustang owners are all switching to speed density? I heard in Mustangs the MAF system is better than SD?
And why would anybody think an ugly peice of plastic attached to the intake ducting makes it better looking?

------------------
'88 IROC TPI 355, '69 truck 4-bolt, fully balanced, 9.75:1 compression, fully ported '70 truck heads(for now), Harland Sharp 1.6 Roller Rockers, Comp Cams CS 252AH-12, ported '86 TPI converted to speed density, Crane AFPR, Flowmaster 3in. exhaust, Edelbrock TES headers, all emissions equipment is still intact, plan on burning my own chips, many more mods and parts on the way as time and money permits =(
Best E.T. with TBI 305: 16.11 @ 82mph
Haven't been to track with new motor
If you have any questions on converting from TBI to TPI email me at jdkchevy70@yahoo.com
In memory of Dale Earnhardt, I'll miss cheering for that black #3 on raceday!!!

IROCZ88

Put on a good set of heads and a decent cam and MAF won't make sufficient adjustments. You'll still have to go out and buy a good custom prom. With the money you spend on that, you buy the equipment to burn chips and have a lifetime of infinite adjustments. Buying one custom prom is like buying a brand new carb and not being able to adjust it. SD with burning equipment is like having a set of metering rods and jets to swap for tuning.


------------------
'88 IROC TPI 355, '69 truck 4-bolt, fully balanced, 9.75:1 compression, fully ported '70 truck heads(for now), Harland Sharp 1.6 Roller Rockers, Comp Cams CS 252AH-12, ported '86 TPI converted to speed density, Crane AFPR, Flowmaster 3in. exhaust, Edelbrock TES headers, all emissions equipment is still intact, plan on burning my own chips, many more mods and parts on the way as time and money permits =(
Best E.T. with TBI 305: 16.11 @ 82mph
Haven't been to track with new motor
If you have any questions on converting from TBI to TPI email me at jdkchevy70@yahoo.com
In memory of Dale Earnhardt, I'll miss cheering for that black #3 on raceday!!!

burnoutrpm

This may be true, but if you put a cam with larger than a 220 duration you have to modify the chip to compensate for that anyway!! You're arguement isn't very realistic because anyone upgrading....cam, heads, injectors.....is going to want a custom chip....regardless of whether they have MAF or SD!

JoelOl75

And the fact that mafs are a restriction holds true no more. Pick up the new car craft. They show that granatelli is adapting larger ford meters to the older tpi cars.

IROCZ88

That's not the point I was trying to get across. All I'm saying is if you're going to do enough mods to require a chip swap you're better off with speed density because you can continue to burn them yourself. With MAF, you can do a whole host of mods, than spend $350 on a custom chip. What happens if you do some more mods and your custom chip doesn't cut it anymore. Spend another $350? If you had SD, you could make the changes in the prom yourself with help from this website.
By the way, Car Craft also said the '85-'89 GM MAF Computers lack adaptive learning capabilities. That basically means the older computers were slow.
Oh yeah, how many people have you seen post, "How can I convert my '90-'92 Speed Density TPI to MAF?" It doesn't happen because those with speed density are happy with it and see no reason to change. However, I've seen many posts stating, "How can I convert my MAF to '90-'92 Speed Density?" Why would people ask this question all the time if MAF is so great and adapts to all mods. There would be no reason for them to even think about it.



------------------
'88 IROC TPI 355, '69 truck 4-bolt, fully balanced, 9.75:1 compression, fully ported '70 truck heads(for now), Harland Sharp 1.6 Roller Rockers, Comp Cams CS 252AH-12, ported '86 TPI converted to speed density, Crane AFPR, Flowmaster 3in. exhaust, Edelbrock TES headers, all emissions equipment is still intact, plan on burning my own chips, many more mods and parts on the way as time and money permits =(
Best E.T. with TBI 305: 16.11 @ 82mph
Haven't been to track with new motor
If you have any questions on converting from TBI to TPI email me at jdkchevy70@yahoo.com
In memory of Dale Earnhardt, I'll miss cheering for that black #3 on raceday!!!

86TpiTransAm

The people that ask that question are the ones that THINK SD is better than MAF when in reality the difference between the two is minimal!! I have MAF and you don't see me askin' that question! That's because I know that my MAF is sufficient enough!! GM wouldn't have switched back to MAF if they actually thought SD was so much better!! I understand that 4th gen MAF is better than 3rd gen MAF but it was GM themselves that said overall SD was less reliable than MAF!! And I agree!!



[This message has been edited by 86TpiTransAm (edited April 07, 2001).]

Guest

Theres so much here... I'll just start at the top!

The MAF only adjusts to a point... I can guarantee you if you throw a cam with 224 intake duration in a MAF car it wont like it much, and you will be doing some chip swapping. With the SD actually you only have to reprogram not replace, and its much more tolerant to mods than everyone says.

Since when? Actually for a long time they have been swapping from the earlier SD to the MAF system, which is nothing like MAF system used on thirdgen F-bodies. Its like the 94-up GM setup, which just goes to show again how far behind the times GM is. The only guys I know of with Mustangs wanting to go SD is those running 10's and faster, simply because the stock ECM is hard to deal with from a programming standpoint. I dont care what car you have, when you get into the 11's you are looking at programming to get the car running optimal. You also neglected to mention that they are not going to the factory SD setup, but rather the aftermarket ones... Like I said, ease of programming.


Theres not much difference. I bet it would work fine.
And I think the 'fix' isnt difficult.


Oh boy... LOTS of misinformation here!
First, you have to be careful what you read sometimes. Car Crapped is WRONG! The MAF system DOES adjust and DOES learn, thats what block learn and integrator are in the stuff you see with a scan tool. It has ZIP to do with processor speed. And if you had been paying attention, you would find that you can program a MAF car just like you can program a SD car, theres no difference to the process required to do so at all.


BTW Kevin is totally right about switching to the 89 MAF code if you are running a MAF system. Its a world better than the 86-88 stuff.

Oh yea, and as for which is better... well that IMO depends on what you have. If you have a MAF and arent running 11's, I'd say stick with it. If you are running faster than that, you would have to do some actual effort to make it work well IMO. Doesnt mean it cant be done though. I see little reason to swap to a SD setup unless its just laying around and you have nothing better to do than rewire and repin stuff.

[This message has been edited by madmax (edited April 07, 2001).]

IROCZTWENTYGR8

iTrader: (1)

I agree with all that, many things I thought and have said before are correct about MAF, cool post MM.

------------------
Looking For:

87 IROC-Z28 350 TPI
The car I want.

84 TRANS AM 305 H.O.
Another car that would be OK to own while I still look for the IROC-Z!!

86TpiTransAm

That's what I'm tryin' to say!! Madmax just said it much much better than I could have!!

TorchTA

89 MAF code..
ok..
stupid question time.

what the hell you talkin about?

-JT
'Peanut' cammed 86 T/A-305 TPI, etc...

Grim Reaper

The 1989 MAF was the best of the MAF systems and the "ARAP" BIN is the best of the stock GM programming for the 1989 MAF cars.

Basically, if you have a 1989 MAF car, most "prom burning guys" start with the ARAP bin and use that as their base.

The ARAP BIN was some special eprom BIN that GM developed for their 1989 test cars which was still emissions compliant.

If you have a pre-1989 MAF car, a lot of guys find converting their MAF car to this version works better.

IROCZTWENTYGR8

iTrader: (1)

What are the advantages of doing that to the 9th injector??

------------------
Looking For:

87 IROC-Z28 350 TPI
The car I want.

84 TRANS AM 305 H.O.
Another car that would be OK to own while I still look for the IROC-Z!!

[This message has been edited by IROCZTWENTYGR8 (edited April 11, 2001).]

F22Raptor

Does anybody have any idea how much would it be to buy a new wiring harness and ECM from a GM dealer for a SD system?. I have a Sunpro scanner than won't read the BLM/INT, AFR, PE%, Knock retard among many other parameters on my 88 GTA, but it will read all those on a 90 and up speed density. I have no tuning capabilities with this scanner and the MAF system.
MAF sucks!
Rick

F22Raptor

the reason i wanna switch is i already bought the scanner ($300) but it is useless with maf and i won't buy me another scanner for SD. I rather buy me the more sophisticated SD system that I can use my scanner with.
does that make sense?
Rick

IROCZTWENTYGR8

iTrader: (1)

MAF doesn't suck dude, have u been reading our posts??

------------------
Looking For:

87 IROC-Z28 350 TPI
The car I want.

84 TRANS AM 305 H.O.
Another car that would be OK to own while I still look for the IROC-Z!!

Grim Reaper

Raptor, why not grab an SD system off an 3.1 MPFI 90-92 F-body. L98/LB9 would be perfect, but the wrecking yards want you to generally take the "WHOLE THING". Whereas they will piece meal the 3.1s system and let it go cheap too.

Also, other 3.1s MPFIs will work, but the actual connectors and length will vary and you may have to do some "cutting and splicing". Luminas, Corsicas, Berrettas, Grand Ams, to name a few...basically any GM car with a 3.1 MPFI except the W Bodies (forget which one that is, but just check the 4th digit for a W).

Then, all you have to do is add a MAP sensor off a vacuum line, an SD L98 or LB9 memcal (depending on your engine) and (I can't remember if yours had the cold start injector) but if it does, just block it off and disable it.

Should be cheaper than replacing a MAF sensor and not terribly hard.

F22Raptor

Hey "dude", just because you say it doesn't suck that doesn't mean I have to believe you.
It sucks big time; been dealing with it for 7 years and it just plain sucks

F22Raptor

Thanks Glenn. Always available, thanks

IROCZTWENTYGR8

iTrader: (1)

If it still isn't working for u, then u either don't know what u are doing or your car needs work. I have MAF and it works really good, and it does for many others also, go and read all of the posts and especially MM's.

------------------
Looking For:

87 IROC-Z28 350 TPI
The car I want.

84 TRANS AM 305 H.O.
Another car that would be OK to own while I still look for the IROC-Z!!

F22Raptor

Some people like to stick with old technology, but I don't. According to "the people who know", the 730 ecm is more powerful and tuner friendly. I think that enough for me besides the cost of a new MAF sensor, inconvenient to move around the engine bay for a cold air set up, it restricts air supply to the engine, brakes a lot, it's ugly, more stuff to go bad, etc etc

IROCZ88

Misinformation? You're the one that needs to pay attention!! JoelOL75 commented on something said in the new Car Craft and I was simply making my own comment. I don't trust any off the shelf magazine. The MAF does learn and adjust, but it can only do so much because of the limitations of the ancient computer. You're right, the same process is involved, but the SD is much more hacked and a lot easier to get help with. I don't know about you but I'd much rather be out driving my car than sitting in front of my computer looking at codes.
My buddy put AFR heads and an XE cam in his 89 TPI 5.7 IROC. The MAF system did NOT adjust and did NOT learn sufficiently to this mod. He bought a chip from Ed Wright which corrected this problem and the car ran great. Fast as hell!! 13.50's. I'm not saying MAF cars aren't fast. It's just everybody seems to think they'll adjust for everything. MAF does adjust to minor mods, but then again, so does SD.
Ayway, he bought an Edelbrock Intake and SLP runners, and ran into the same problems again. Hesitation under acceleration, poor idle, horrible gas milage. Still ran in the 13.10's. Picked up 3 tenths.
Eventually we put a 730 ecm and map sensor in it. With the stock 305 chip the car didn't run too bad. It was surprising.
He purchased all the necessary burning equipment, and we struggled with a Diacom to try and tune it. It was a pita, but we eventually got the car to very smooth, good idle, 20+mpg. Took it to Numidia and it ran 13.15. Not any faster at WOT, but part throttle it's a lot more pleasant.
I'm not saying we couldn't have done this with his MAF, but it was great to look in the DIY prom board archives and find every bit of advice and information we needed.
Now we're working on my car and making a lot of progress. I'm getting 25 mpg, and it runs great through the entire powerband. I'll stick with SD. It would be great to have some more info on MAF proms. Lack of knowledge and info is why I converted mine to SD.




------------------
'88 IROC TPI 355, '69 truck 4-bolt, fully balanced, 9.75:1 compression, fully ported '70 truck heads(for now), Harland Sharp 1.6 Roller Rockers, Comp Cams CS 252AH-12, ported '86 TPI converted to speed density, Crane AFPR, Flowmaster 3in. exhaust, Edelbrock TES headers, all emissions equipment is still intact, plan on burning my own chips, many more mods and parts on the way as time and money permits =(
Best E.T. with TBI 305: 16.11 @ 82mph
Haven't been to track with new motor
If you have any questions on converting from TBI to TPI email me at jdkchevy70@yahoo.com
In memory of Dale Earnhardt, I'll miss cheering for that black #3 on raceday!!!

IROCZ88

BTW, ask Kevin91z how far you can go with the stock SD prom. His probably adjusted just as much as a MAF car would without needing PROM work.

IROCZTWENTYGR8

iTrader: (1)

The 730 ECM is better than the MAF's, but there will be a fix for the MAF's ECM in a while. I have always read everywhere that MAF is much better with mods then SD is and I also think MAF looks better then SD, MO. I'm also not going keep repeating myself and what others have said here and in other posts when they can look themselves.

------------------
Looking For:

87 IROC-Z28 350 TPI
The car I want.

84 TRANS AM 305 H.O.
Another car that would be OK to own while I still look for the IROC-Z!!

Guest

Kevin is a friend of mine, Ive been in his car and I know all about it. His 'stock' chip wasnt exactly stock, it was changed. He was having problems with it running too rich.

And no need to flame me about Car Craft, I am just correcting their obvious mistake. And I dont understand what you are saying about ancient computer and limited learning capability... It works just fine. Its far from stone age like it seems you are trying to make it out to be.

The 7165 is hacked too, just not as much. Thing is, tunercat has a definition file for it, so its no more difficult to change parameters. There have been things added as well, and there are probably still a few things missing from it. That doesnt mean it cant be used, and isnt friendly, it just takes a little more effort. So what. And I never said it adjusted to any mod... hell I already know it doesnt. I figured with the cam I was going to use, the stock computer wouldnt like it, and as it turned out, it did just what I suspected and didnt like it.

IMO, running MAF is no big deal. Lots of people like to take the easy route, throw their hands up in the air and swap to SD, or ditch the computer altogether. You are right, it would be nice if people spent more time on figuring out how to make it work well. I have been doing that, and you chastise me for it Vader quite obviously is spending time on it, and I'm sure there are others. Right now, I dont see a pressing need to swap to a SD setup unless you feel like doing it and have it laying around. Seems too many people are ready to swap over no matter the cost, and then dont run much if any better at all. Theres no doubt that there were improvements made, but if the car doesnt run any faster, and the driveability is fine (the car I am working on runs just fine, nothing wrong with mileage) then what is the point? I still say that it doesnt make any sense from a time or financial standpoint to swap over to the SD unless you have the free time, and you have parts laying around, or you just feel like throwing money at your car.

Heres why I stand where I do:
I have owned 3 MAF cars now.
None of them actually had the MAF go bad, ever. Thats on 3 cars. A total of 21 years of ownership if you wanna look at it in terms of time.
The one I have actually tried to make into a fast car is still running a stock plenum, stock runners, stock tb, no airfoil, and a slightly modified base and it should at the very least be running mid-low 13's right now. On a super hot day, it ran 14.2 and thats before I swapped the manifold and chip and picked up 25+ hp, not to mention the y-pipe is a joke and leaves much to be desired. Ill have to wait for the track to get an actual new time, but I have no doubts its going to be well into the 13's. Maybe I'll be pleasantly surprised. It doesnt have any driveability problems, gets decent mileage, and I see no reason to go in there and repin the harness, try to fit the SD ecm in there (pretty sure it wont) and buy whatever parts I need so I can put the MAF on a shelf.
The only thing I'll admit to is it does suck having to find a place in the intake tract to put it, but thats a minor inconvience IMO.

IROCZTWENTYGR8

iTrader: (1)

Exactly, another good post MM.

------------------
Looking For:

87 IROC-Z28 350 TPI
The car I want.

84 TRANS AM 305 H.O.
Another car that would be OK to own while I still look for the IROC-Z!!

[This message has been edited by IROCZTWENTYGR8 (edited April 11, 2001).]

Guest

By the way, I'm not faulting anyone here for changing over to SD, it just doesnt make much sense anymore IMO since the stuff we know now about the MAF and how to work with it make the differences between the two less significant.

raging86

lots of great info here. looks like the moderators and other smarties have stepped in and done us all a big favor. i have read and understood all of this post and the one awhile ago about the actual maf sensor not flowin enough. the only thing i still don't understand is the part about the 89 maf being the best. r you talking about the PROM chip being better or the whole ecm? the chip burning is easier on the 89 PROM? i have an 86 and will in a few years be dropping in a 383 with a superram. i'm lookin for about 400 horse. i want to keep the maf system, so i'll have to see about a better flowing maf (who knows what will come along in a year or so) but what will i have to do as far as software? i'll have to burn a new chip, and that is where the improved 89 stuff comes in and i get lost. i think explaining the differences in the 89 system as it pertains to actual modification process will make it clearer for me(and possibly others) to understand, instead of using all jargon i'm not familiar with. i'm just not understanding how the 89 system is different, and how it is easier to modify. i really appreciate you guys taking time to help us more ignorant folks out.

------------------
86 IROCZ
T-Tops
700R4
305 TPI
3.23 gears
shift kit, manual TC switch, manual fan switch, flowmaster exhaust with edelbrock TES headers& hollow cat, gutted MAF.

Guest

Actually the 89 isnt any easier to modify really, it just works better.

All you need is the chip itself, thats the plastic piece you stick into the ecm. If you have a burner, you could use the chip from an 86-88 and put the 89 programming code on the EPROM (thats a part inside the chip) and run that, which is what I did.

Read TRAX's article about chip burning. It will help. I'm thinking about making an Idiot's Guide to Chip Burning, maybe make things a little easier to comprehend... all I need is the time to do that. I've been there myself, but looking back it wasnt difficult to do it was just confusing since I hadnt done it before and nobody was showing me how.

IROCZ88

In previous posts Kevin91z said he was using the stock 305 5-spd PROM. My bad, I don't know him personally.
I think it's great that there are people trying to figure the MAF out. If you guys get it as easy as the SD then I might play around MAF in the future. I still have an 86 ecm and wiring harness.
Knowledge is the key, and right now there is more known about SD, plus most aftermarket parts are SD, and it is better if you're putting a TPI in a street rod which is my next project.
I don't believe SD is faster, just more convenient. My friends IROC was faster at the track with an out of tune MAF than his tuned SD. Whatever you have, stick with it. MM, let us know how your progress is going and let us know if tunercat comes out with new MAF softerware.
BTW, I still think the MAF computers are ancient, I also think the 90-92 SD density computers are ancient. Look at what they have now in the LS1.

IROCZTWENTYGR8

iTrader: (1)

Yes, that would be cool!!


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Looking For:

87 IROC-Z28 350 TPI
The car I want.

84 TRANS AM 305 H.O.
Another car that would be OK to own while I still look for the IROC-Z!!

IROCZ88

PLEASE!! An idiots guide would be great!!! I've just been tuning two chips I got out of a junkyard. I don't understand the part in Traxions article about ordering the new PROMS and modifying pins, and a bunch of other stuff I can't think of off the top pf my head.

IROCZ88

BTW, did you ever make a prom that took a **** on you while you were driving? I did, and I was stuck in limp mode on the way home. Don't know how I managed to do that one.

raging86

hey madmax, thanx for clearin that up for me. maybe i made it sound like i'm dumber than i really am, i know what a PROM is and how it works, and the memcal and all that other stuff, i just wasn't trackin with that stuff about the 89. i read traxion's article and it interested me greatly in chip burning. i may try it, even though my motor is mostly stock. i can change my the temp when my fan comes on and stuff like that, and when i swap in my new 6 speed i can burn my own prom for that. by startin with simple stuff i'll get good at it so in a couple of years when i graduate college and build my 383 i'll be set to go!!! hey maybe i can trick some of my friends into lettin me make chips for them too. i already have access a GM TECH II scanner. (i'm kind of excited about learning more if you couldn't tell) thanks alot for helpin me out!

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86 IROCZ
T-Tops
700R4
305 TPI
3.23 gears
shift kit, manual TC switch, manual fan switch, flowmaster exhaust with edelbrock TES headers& hollow cat, gutted MAF.

Grim Reaper

Raging, learning on a basically stock engine is the PERFECT place to learn. And yes, you can greatly improve your performance, driveability, responsiveness and fuel economy.

If I still had to test my car for emissions, I am sure I am producing less also.

And there is a heck of a lot more to play with than you can imagine. At some point, you may even find that you not only want to change the parameters, but the actual machine instructions to make it work even better than the way GM designed it.